package com.seu.data.structures.hashtable.leetcode;

/**
 * 查找一个字符串中第一个只出现一次的字符的序号
 *
 * @author liangfeihu
 * @since 2018/12/8 11:10
 */
class Solution {

    public int firstUniqChar(String s) {

        int[] freq = new int[26];
        for (int i = 0; i < s.length(); i++) {
            freq[s.charAt(i) - 'a']++;
        }

        for (int i = 0; i < s.length(); i++) {
            if (freq[s.charAt(i) - 'a'] == 1) {
                return i;
            }
        }

        return -1;
    }

}
